Outlet-box.



N0. 826,072. PATENTED JULY 17, 1906.

R. McK. THOMAS.

v OUTLET BOX.

APPLICATION FILED JULYB. 1905.

@Witnesses v QZISWMM Suva 11 ["oz UNITED STATES PATENT OFFICE.

ROBERT MCKEAN THOMAS, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THOMAS & BETTS OO., OF NEW YORK, N. Y., 'A CORPORATION OF NEW YORK.

OUTLET-BOX.

Specification of Letters Patent.

PatentedJ'uIy 17, 1906.

To all, whom t may concern.-

Be it known that I, ROBERT MCKEAN THOMAS, of Elizabeth, New Jersey, have invented certain `Improvements in Outlet- Boxes, of which the following description, in connection with the accompanying drawings, is a specification, like numerals on the drawings designating like parts.

Y This invention relates to outlet-.boxes for electrical conduits, and has for its object the provision of a box containing knock-outs or portions which may be removed readily by a ammer or thelike, the principal features of my invention relating to the mode of securing these knock-outs so-that they will be retained firmly in place until the need for their removal arises, my method for accomplishing this and the means utilized presenting certain features of noveltiylwhich will be hereinafter illustrated and lly described, and

y pointed out in the claims.

In the drawings, Figure 1 illustrates in pe spective an outlet-box in the construction of which my inventionl has been embodied. Fig. 2 is a sectional view on the line 2 2, Fig. 1, showing on an enlarged scale a portion of one wall of the box with theknock-outs in place. Fig. 3 is a view similar to Fig. 2 of a modification of my invention.

In the embodiment of my invention selected for illustration and description as a convenient form of construction to enable ready and complete understandin of my improvements the part designated y the referencenumeral 1 is the side wall of a box, which may be made of any suitable material, preferably sheet-steel, and from which portions 2 have been removed by punching or in any suitable manner and reinserted loosely, as best seen in Fig. 2.

In accordance with my invention to retain these knock-out portions in lace I subayer 3 of a suitable material, preferably zinc, Will be deposited at the joint 4, filling the interstices thereof and binding the knock-out to the adjoining Wall 1, the covering preferably being a substantial layer extending over the entire surface of the box. When thus coated, either by zinc or the like, ap lied, preferably, in molten form or electrica ly or eot the box to a coatingprocess y which a box, as indicated at 5 in Fig. 1 and seen tobetter advantage in Fig. 3, by any suitable means-as, for exam le, by the use of an annular die similar to the end of a pi e-as an additional precaution to secure the ook-out in place, and this may be used in conjunction 4with the retaining-layer, as indicated by the numeral 6 in Fig. 3 on the u per side, or Without such layer, as indicate at the lower side in said Fi 3.

Insteac of a single relatively broad annular depression I may secure the same result by two concentric annular de ressions, as indicated at 7 in Fig. 3, one o Which is adjacent to the periphery of the knock-out and in the material of the latter, While the other depression is in the wall of the box near the aperture containing the knock-out. This form of knock-out may also be used with or v'ithout the retaining layer, as indicated in Having described my invention thus fully, it will be understood that I do not limit myself to the exact form of construction or to the exact material shown and described nor in general otherwise than as set forth in the claims read in connection with this specification.`

. What I claim, and desire to secure by Letters Patent, is-

1. The combination with an outlet-box provided with an aperture, of a knock-out portion held in place to cover said aperture by suitable extraneous fastening material, substantially as described.

2. The combination with an outlet-box provided with an aperture, of a knock-out portion held in place within said aperture by extraneous fastening material applied at the IOO region of union between the edges of said knock-out and aperture, substantially as described. j

3. An outlet-box rovided with a knockout portion held in p ace by a layer of zinc.

4. An outlet-box provided with knock-out portions held in place b a la er of extraneous fastening materia app ied after the knock-out portions have been removed and returned.

5. The method of securing a knock-out in place in electrical conduit appliances consisting in depositing extraneous plastic fastening.

material upon the region of juncture between said knock-out portion and the adjacent wall.

6. The method of securin a knock-out i'n the wall of an electrical con uit appliance or in a similar device, consisting in swaging together the material of said knock-out and Wall at its juncture and applying fastening zo material thereto at such region of juncture, substantially as described.

7. The method of securing a knock-out in the wall of an electrical conduit member of the class described, consisting in de ositing a continuous layer of extraneous p astio fastening material over said knock-out and the adjacent walls of said member, substantially as described.

Signed at New York, in the countv of New 3o York and State of New York, this 29th day of June, A. D. 1905.

ROBERT MoKEAN THOMAS.

Witnesses:

ALEXANDER C. PROUDFIT, LoUIs LEVINE. 

